The popularity of electronically presented content items, such as video games and other media items, has increased dramatically in recent years. In some examples, in order to attract more players and increase the popularity of their games, video game designers may create intricate virtual game worlds having rich detail and visual features. One important aspect of a virtual game world is the design of its terrain. Video game designers may often spend considerable time and effort on terrain design. In some cases, designers may edit features related to terrain height, terrain vegetation, terrain textures, terrain layers, and other terrain features. Because terrain design may often require considerable amounts of work, it may often require multiple designers and other users to participate in the process and work together with one another. However, conventional development interfaces may often be limited with respect to their ability to allow effective collaboration between terrain designers. For example, conventional development interfaces may operate by storing terrain data in a single large file that may that reduce the effectiveness of multiple users collaborating simultaneously, or outright prevent it. This may increase the cost and complexity of the game development process and result in undesirable confusion and delays.